Improvement in sewing-machine



T. LAM B.

Sewing Machine.

- V2 Sheets-Sheet 1. l.

n. FETERS. Mwwnwr. Washington DJ;

2 Sheets-Sheet 2. T. LAMB.

Sewing Machine.

Patent-ed Dec. 28, 1869.

tnited Cie-taten :me aan.

kLette/rs Patent No. 98,390, dated December 28, 1869.

IMPRVEMENT IN SEWING-MACHINE.

' The Schedule referred to in these Letters Patent and making part ofthe same ATo all whom fit 'may concern Be it known that I, THOMAS LAMB,of Philadelphia, Pennsylvania, have invented certain Improvements inSewing-Machines; and Ido hereby declare the following to be a full,clear, andrexact description o f the same.

My invention consists of' certain improvements, fully describedhereaften'in that class of lock-stitch sewingmachines, in whichdiscoidal shuttles are used.

In order to enable others skilled in the art to make and usc myinvention, I will now proceed t0l describe its construction andoperation, reference being had to the accompanying drawing, which formsa part of this specification, and in which- Figure 1 is a longitudinalsectional view lof' my improved sewing-machine 5 Figure 2, an end viewofthe same;

Figure 3, transverse section on the line 1 2, fig. 1,

looking in the direction of the arrow;

Figure 4, a plan View, showing the edge ofthe shuttie;

Figures 5, 6, and 7, detached views, illustrating my' invention; and

Figure S, a modification.

Similar letters refer to similar parts throughout the different views. e

A is the base-plate of the machine, in projections a c, beneath whichturns the driving-shaft B, the latter being provided, near its rear end,wit-h an eccentric, C,

by meansv of which, and an arm, X, shown by dotted' lines in iig. 1, thenecessary reciprocating motion is imparted to the needle-arm D.

At the front end ofthe shaft B isa forked -driver, c, by which thediscoidal shuttle F is rotated, the latter being arranged at an angle,as shown in iig. 1, and turning in an inclined race.

.'lhis shuttle-race consists of two plates E and E, each of which iscurved so as to fit against and enter a groove of the shuttle, the twoplates being secured to a hanger, M, which projects at` an angle fromthe underside of the base-plate.

In consequence of the inclination of the shuttle-race, the prongs of thedriver, as they rotate, alternately enter and are withdrawn from holes bb on the face of the shuttle, neither ot' them being in permanentcontact with the latter, and offering no obstruction to the passage ofthe'loop of needle-thread around the shut tie, as will be more fullydescribed hereafter.

The nose or hook el of the shuttle is formed by cutting away a portionot' the circumference ofthe same, as clearly shown in ig. 4, and,secured to the centre of the inner face of the shuttle, by a screw o'rotherwise, isv an adjustable projection or hook, e, having, at its outerend, a bevelled edge, e', for a purpose described hereafter4 At theupper end of the plate E of the shuttle-race is a bevelled project-ion,f, the object of which is to push the loop of needle-thread over thehook d, and to direct it to each side of the shuttle, as shown in fig.2.

. A rod, h, is secured to the plate E of the race, and

projects over a portion of' the inner face of the shuttle,

and on the opposite side of the shuttle is a recess for the reception ofa bobbin, G, which, in the present instance, is held invits place by aplate or case, i, the edge' of which tits loosely in a groove in the`shuttle, the case, however, not turning with the latter.

The shuttle-thread from the bobbin G passes through one or more openingsi in the plate i, according to the tension required.

The presser-foot H is attached to one end of a recessed arm, I, which iscurved in the arc of a-circle, and secured, at its opposite end, to aplate, J, the latter being arranged to turn upon trunnions jj of thebase-plate, and being elevated, at its rear end, by a spring, k, whichtends to hold the presser-foot down to the work-plate l.

The feeding-dog K is also secured to a curved arm, L, which is arrangedto slide in the recess m of the arm I.

A lug, p, is attached to the needle-arm D by a setscrew, or otherwise,so that it may readily be adjusted thereon, and is arranged, when theneedle-arm is raised, to strike a pin, qfg. -7, which enters thevvrecess m of the arm I, and has secured to it, within the said recess,a wedge-shaped block, q'.

One side of this block q bears against theinclined end of the arm L, andits opposite side against the i11- clined end of a plate, r, which isslotted, and has a slight motion within the recess m, limited by a pin,o".

A spring, s, of the arm I, rigs. 2 and 3, bears against one side ot' thefeeding-dog arm, andtends to push it from the recess m, the feed beingePected bya lateral pressure in the opposite direction, imparted by alever, t, which is hung to the arm I.

The lever t is provided with a curved arm, t, which partly embraces theneedle-arm, so that when the latter is raised, a pin, u, ofthe same,shall strike and turn the arrn t', causing the lever t to bear againstand operate the feed-dog K.

Operation.

When the needle descends through the fabric to be sewed, and toward theshuttle, the hook d of the latter passes between the needle and itsthread, and carries the loop toward the bevelled projection f, which, asbefere mentioned, pushes the loop back on to the hook d, and directs itVto each side of the` shuttle, as

seen in iigs. 2, 3, and 4.

The shuttle continues to revolve, carrying the loop with it, and the'needle descends to the lowest point,

and again rises until it is entirely,witlidrawn from the cloth, as shownin fig. 5, at which time the presser-foot H is raised, and the feed-dogK depressed and moved laterally to a sufficient extent to eiect thedesired change of position of'the cloth.

These motions of the presser-foot and feed-dog are eiectedsimultaneously, as the needle is raised, by the lug p and pin u of theneedle-arm, as I will now pro ceed to explain.

The lug p strikes the pin q, and forces the wedgeshaped block g into therecess on' of the arm I, the block bearing upon and causing the plate rand arm J to move in the direction of their respective arrows,

rlhe motion of the plate r is arrested by the pin r',

the plate J then turning upon its trunnions j untilthe arm I is movedsuliiciently to raise the presser-foot Y clear of the cloth, as shown iniig. 2.

.llhe arm L is in the mean time moved'iu a contrary direction, causingthe feed-dog to bear upon the cloth. l

As soon as these motions are perfected, the pin u Yof theneedle-arm`strikes the arm t of the lever t, and

causes the latter to bear upon and move the feed-dog laterally to therequired extent.

When the needle again descends, the block q' is again released, and thespring k of the plate J bears upon the bed-plate, turns the arm I, anddepresses the foot H until it again bears upon the cloth.

At the same time the pin u descends, releasing the lever t, andpermitting the feed-dog to regain its former position by the action ofthe spring s. (See g. 3.)

As the needle descends through the cloth a second time, the irst loop isthrown oli' from the shuttle by the bevelled edge e ofthe hook e, asshown on fig. 6, and the loop, when thus detached, is prevented frombecoming entangledwith the driver C by the rodjl,

which holds it close to the shuttle.

As the needle continues to descend, a second loop is caught by theshuttle-hook, and carried round, the first loop, together with theinterlocked shuttle-thread from the bobbin G, being carried up into ,thecloth.

The second loop is in like manner thrown oii from the shuttle, and drawnup and-interlocked with the shuttle-thread as a third loop is formed,the operation being repeated and continued until the required num berot' stitches have been made.

A most important point is the fact that the bobbin G is stationary, anddoes not revolve with the shuttle, being merely held against it by theplate t'. In' consequence of this arrangement, the shuttle-thread is notcarried around and twisted, but is fed through the,holes t', in the samecondition in which it is wound on the bobbin, the complicated devicesfor taking the twist out the under serrated surface of l the rear end ofthe machine, the presence of operatingof the shuttle-thread, whichrender machines of this class so objectionable, being entirely dispensedwith.

Another plan of holding the bobbin up to the shuttle is illustrated infig. 8. contained within a cup-shaped plate, t', which is held in itsplace by a light spriugrod, y, secured to the under side of thebed-plate, the pressure of which rod is, however, not sniicient toprevent the free passage of the loop of needle-thread between it andlthecup.

Although the thread which passes through the openings in the plate t'will generally prevent the latter from. turning, it may be rendered moresecure by a finger, W, iig. l, extending from the base-plate A, andbearing against a projecting portion of the plate t', the

needle-thread passing between the tin ger and the plateA as it iscarried round the shuttle.

On account of the adjustability of the hook e, its position in regard tothe points of the shuttle may be regulated with the nicety required.

By operating the presser-foot and feedingaiog from devices over theworkplate, where they interfere with movements of the operator, isavoided.

I claim as-my invention,iand desire to secure by Letters Patenty 1. Ashuttle, F, having a hook, d, at the edge, and a book, e, at the back,and revolving' in an inclined shuttle-race, in combination with abobbin, G, which lies within a perforated case, retained in a stationaryposition loosely within the shuttle, as described.

2. The hook c, bevelled at the edge, arranged at the back of theshuttle, so as to be adjustable ou the same, and operating substantiallyas specified.

3. A projection, f, arranged in respect to the shuttle, substantially asand for the purpose set forth.

4. The presserfoot, attached to an arm vibrating on a fulcrum at therear. end of the machine, and operated by the Yneedle-arm, as described.

5. A feeding-foot, K, attached to an overhanging arm, pivoted at therear end of the machine, and operated vertically and laterally'from theneedle-arm by devices substantially as described, and for the purposespecified.

6. The arm I, hung to the base-plate A, and carrying the arm L and slider, in combination with a wedge, q', which is forced between the slideand the arm L ou the movement of the needle-arm, substantially as andfor the purpose specified.

In testimony whereof, I have signed my name to this specification, inthe presence of' two subscribing witnesses.

Witnesses: THOS. LAMB.

JOHN WHITE, HARRY SMITH.

In this case the bobbiu is

